Ask most nearlyweds how much wedding cake they need and the answer comes back fast: however many guests are on the list. It is an understandable starting point, but when it comes to wedding cake serving sizes, ordering for your full headcount is almost always more than you actually need. In reality, typically only 60 to 70 per cent of wedding guests eat cake on the day. Weddings are busy, fast-moving days, and by the time the cake is cut some guests are still delightfully full from dinner, others are deep in conversation at the bar, and a few have found their way to the dance floor and are not coming back. It is not that they do not want cake - it is just that a wedding moves quickly and the cake does not always reach everyone in the room. Order for your entire guest list and you will almost certainly end up with more wedding cake portions than you need, which is not exactly a disaster (hello, wedding cake for breakfast) but it does mean spending more of your budget than you had to.
One more thing worth knowing before you start comparing wedding cake sizes: our cakes are cut into 2-inch square party portions rather than the larger triangular slices you might be picturing, which means each tier goes further than its dimensions suggest. A 10-inch single tier, for example, serves 54 guests at party portions - considerably more than most couples expect. Here are the honest numbers to work from, based on real wedding cake portion sizes rather than the overly generous estimates you will find on most sizing guides.
How many portions do you actually need? Start here.
The simplest way to calculate your wedding cake portions is to take your total guest count and multiply it by 0.65. That gives you a realistic estimate of how many people will actually eat cake on the day.
For 80 guests - around 52 portions.
For 100 guests - around 65 portions.
For 120 guests - around 78 portions.
Those numbers tend to feel smaller than nearlyweds expect, but they consistently reflect what actually happens at weddings of every size, from intimate London ceremonies to larger wedding receptions across Surrey, Hertfordshire, Buckinghamshire, Berkshire, Kent and Essex. Working from them rather than your full headcount means you end up with just the right amount rather than boxes going home with the wedding party at the end of the night.
It is also a handy trick to factor in when the cake is actually being served. If it is coming out as dessert while everyone is still seated, uptake will be higher because it is part of the meal and nobody has to go looking for it. Cut it later in the evening once the dancing has started and the bar has been open for a while, and you will sit at the lower end of that 60 to 70 per cent range. Both are completely fine to plan around - you just need to know which one applies to your day.
60–70% of wedding guests typically eat cake on the day. Order for that number, not the full guest list.
Wedding cake size guide: how many does each tier serve?
All portions are cut into 2-inch squares. Use the wedding cake serving chart below as your starting point - it shows how our full range of wedding cake tier sizes, from a single-tier 6-inch up to our largest three-tier combination, maps to real guest numbers based on that 65 per cent uptake rate. These are the wedding cake serving sizes we recommend to every couple who orders with us.
| Cake | Portions | Good for |
|---|---|---|
| Small 6" | 19 | Weddings of up to around 30 guests, or as the top tier in a multi-tier cake |
| Medium 8" | 34 | Small weddings up to 40 guests (accounting for real uptake) |
| Large 10" | 54 | Weddings of around 60–70 guests |
| Extra Large 12" | 77 | Weddings of around 90–100 guests |
| Two Tier 6" + 8" | 53 | A practical choice for 60–70 guests who want the look of a tiered cake |
| Three Tier 6" + 8" + 10" | 107 | Up to 120+ guests when paired with an additional single tier |
Our three-tier wedding cake at 107 portions covers the vast majority of weddings comfortably and is the most popular choice for guest lists of 80 to 120 across London and the surrounding counties. For guest lists above that, the most practical solution is to pair the three-tier show cake with one or more additional single tiers in the same flavour. The show cake stays at the centre of the table looking exactly as it should, and the extra tiers are cut and served alongside it. It is the simplest way to scale up without overcomplicating the order.
Finger portions vs dessert portions - which does your wedding need?
Not all wedding cake portions are the same size, and understanding the difference matters when you are working out how much cake to order. Finger portions - sometimes called party portions - are the standard for evening service. They are slim, usually around 1 inch by 2 inches, and designed to be eaten standing up with a napkin in one hand and a glass of something in the other.
Dessert portions are roughly double the size, closer to a traditional slice you would plate up and eat with a fork. If your wedding cake is being served as the dessert course during the wedding breakfast, dessert portions are the better fit - but you will need more cake to cover the same number of guests.
What to do with leftover wedding cake
Once your wedding cake is cut and served, any remaining slices need to go into an airtight container fairly quickly. Sponge dries out fast once it is exposed to air, and it is the kind of thing that is easy to overlook in the middle of a busy evening. Brief whoever is managing the food on the day before things get going rather than hoping someone remembers at midnight.
Properly stored leftover wedding cake keeps well overnight and, in our experience, disappears very quickly the next morning. If you are staying at the venue, it is worth having a quick conversation with them in advance about where cut cake can be kept so there is already a plan in place by the time the evening winds down. As one of our couples once put it: the wedding cake for breakfast the morning after is genuinely one of the best parts.
If you want to keep leftover wedding cake for longer, sponge freezes surprisingly well. Wrap individual portions tightly in cling film, place them in a freezer bag and they will keep for up to three months. Some couples deliberately set aside a few slices to enjoy on their first anniversary - a modern take on the old tradition of saving the top tier of a fruit cake.
Leftover cake goes straight into an airtight container. Sponge dries out fast once it is cut - brief whoever is managing the food on the day.
Still not sure which wedding cake size is right for you?
If you are working out wedding cake portions for a larger or unusual guest count, or you want a second opinion before you order, our team is happy to help. We deliver wedding cakes to venues across London, Surrey, Hertfordshire, Buckinghamshire, Berkshire, Kent and Essex - all within 80 miles of our bakery in TW8. Tell us your guest count and we will recommend the right size or combination for your day.